Their full name is Haiji Senri (千理 牌示). Their first name Haiji (牌示) means "showing cards". Their surname Senri (千理) is pronounced the same as Tsurubami Senri's surname Senri (闡裡), but with different kanji. The first kanji sen (千) in their surname means "thousand", while the second kanji ri (理) means "logic" or "reason". The surname was copied from the Senri clan, but modified slightly. As such, it is unknown what their original surname was.

Haiji frequently hung around the shrine, and they were one of several people who got a close look at the course of Tsurubami's conquest of Mugenri. Haiji is Tsurubami's biggest fan and idolizes them. On their side, Tsurubami considers them a nuisance.

Tenkai Zuifeng

Haiji seems to be jealous of Tenkai for being Tsurubami's best friend and close confidant. On their side, Tenkai considers them an annoyance.

Since Haiji is a spell collector, they admire spell cards a lot. They are also a huge fan of who introduced the spell card system to Mugenri, the second-generation priest of the Senri Shrine. However, most of Haiji's spell cards are directly based on the spells used by various characters from the Touhou Project, mainly final and extra bosses.